Question

If $3$ is the least prime factor of number $a$ and $7$ is the least prime factor of number $b$, then the least prime factor of $a+b$ is

• A. $2$
• B. $3$
• C. $5$
• D. $10$

Answer 1

The correct option is A $2$

Given:
Least prime factor of $a=3$
Least prime factor of $b=7$
$\therefore$Least prime factor of $(a+b)=2$
$\therefore a+b$ will be always an even number.